Organic rich to moderate black to light grey shale. Some parts of FM-4 are silty shale. Minor rust stains are present on lighter samples. Representative of upper portion of a turbidite sequence.
Shale, foliated, and bearing organic matter, from the interbeds between sandstone layers. Fine grained laminated sands between shales were uncollectible, but present. Friable and fragile.
Thin Section:
Very fine to fine grain, poorly sorted…